Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 605 [Rate centres in NPA 605] [Dial plan for NPA 605]

NXX: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
605-340 A Spearfish SD NWUNSDAA1MD  7421 AT&T - LOCAL 640      
605-340 0 Spearfish SD SXFLSDCHIMD  106F BANDWIDTH.COM CLEC, LLC - SD 640   2010-10-09   
605-340 1 Spearfish SD SXFLSDCOTMD  162G ONVOY, LLC - SD 640   2017-11-04   
605-340 2 Spearfish SD SXFLSDCOTMD  162G ONVOY, LLC - SD 640   2023-08-20   
605-340 4 Spearfish SD RPCYSDCOGMD  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2021-06-06   
605-340 5 Spearfish SD RPCYSDCOGMD  6534 NEW CINGULAR WIRELESS PCS, LLC - IL 640   2019-12-04   
605-340 6 Spearfish SD SXFLSDPS0MD  073H TELNYX LLC 640   2017-03-31   
605-340 8 Spearfish SD SXFLSDCOTMD  162G ONVOY, LLC - SD 640   2012-12-15   
605-340 9 Spearfish SD SXFLSDCOTMD  162G ONVOY, LLC - SD 640   2012-12-15   

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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